Beogram 4004 Type 5526: Output Board Recap and Update

The Beogram 4004 output board has the usual phono signal connector and muting relay but also has circuitry added to allow remote control functionality from a Beomaster such as the Beomaster 2400. For this board I replaced the two electrolytic capacitors with new ones and the two tantalum capacitors with WIMA MKS capacitors. I replaced the muting relay with a new, sealed Omron relay mounted on Beolover's custom adapter (so that it is directly replaceable with the original National relay).

As Beolover typically does I added an optional phono cable grounding switch to the output connector. This switch allows an owner to connect the phono signal shield wires to the Beogram chassis ground or leave them open (as they normally are). The normal configuration is fine when using the Beogram phono DIN connector with a B&O Beomaster (like the 2400). However, when connecting the phono cable to a non-B&O amplifier there is often hum present that requires connecting an extra grounding wire from the Beogram to the amplifier chassis ground lug. This grounding switch eliminates the need for the extra grounding wire.

While the small switch is secured by the leads soldered to the board, I added black hot glue around it to give it extra support. I like that glue for this application because it will provide the needed support but isn't permanent like epoxy glue. The black hot glue can be peeled off in the future if so desired.

This board is a quick task so it is on to turntable mechanical parts for cleaning, lubrication and adjustment.